Transcript for Kate Makes First Public Appearance Post-Birth at Ultra Marathon

The pictures just in. Making their first appearance since baby prince george was born. Abc's lama hasan has more. Reporter: This morning, the duke of cambridge is kicking off the 135-mile ring of fire marathon, bringing along a surprise visitor. This is kate's first public appearance since giving birth to baby george. Wearing some skinny jeans, looking as glam as ever, showing she's shed that baby weight. The next time we see him will be at his christening. Kate and will want to protect george from the spotlight as much as possible. Reporter: The family will be moving into their new home soon. How about harry? The world's most eligible bachelor has made no secret about his desire to settle down. I'm looking for the right person to take over the job. Reporter: The rumor mill is in overdrive about his fame. So, who is cressida or cressi as her friends like to call her. She's comfortable around royalty. She's very aristocratic. She's not like from kate, a middle-class background. Reporter: What's the verdict? Ginger haired dashing prince get on bended knee and pop the question? Is she the one? Cressida could be the one. I don't think even if she is, prince harry will propose to her anytime soon, I'm afraid. Reporter: Perhaps harry isn't quite ready to thrust cressida into the limelight. But she is the one to watch. For "good morning america," lama hasan, abc news, london.

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